i2c: pnx: add device tree support

This patch adds device tree support to the pnx-i2c driver by using platform
resources for memory region and irq and removing dependency on mach includes.

The following platforms are affected:

* PNX
* LPC31xx (WIP)
* LPC32xx

The patch is based on a patch by Jon Smirl, working on lpc31xx integration

Signed-off-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

1 files changed, 47 insertions, 16 deletions

diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c
index f69d80b8d736..99389d2eae51 100644
--- a/drivers/i2c/busses/i2c-pnx.c
+++ b/drivers/i2c/busses/i2c-pnx.c
@@ -23,10 +23,11 @@
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/slab.h>
+#include <linux/of_i2c.h>
 
-#define I2C_PNX_TIMEOUT         10 /* msec */
-#define I2C_PNX_SPEED_KHZ       100
-#define I2C_PNX_REGION_SIZE     0x100
+#define I2C_PNX_TIMEOUT_DEFAULT         10 /* msec */
+#define I2C_PNX_SPEED_KHZ_DEFAULT       100
+#define I2C_PNX_REGION_SIZE             0x100
 
 enum {
         mstatus_tdi = 0x00000001,
@@ -74,8 +75,9 @@ enum {
 #define I2C_REG_TXS(a)  ((a)->ioaddr + 0x28)    /* Tx slave FIFO (RO) */
 #define I2C_REG_STFL(a) ((a)->ioaddr + 0x2c)    /* Tx slave FIFO level (RO) */
 
-static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data)
+static inline int wait_timeout(struct i2c_pnx_algo_data *data)
 {
+        long timeout = data->timeout;
         while (timeout > 0 &&
                         (ioread32(I2C_REG_STS(data)) & mstatus_active)) {
                 mdelay(1);
@@ -84,8 +86,9 @@ static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data)
         return (timeout <= 0);
 }
 
-static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data)
+static inline int wait_reset(struct i2c_pnx_algo_data *data)
 {
+        long timeout = data->timeout;
         while (timeout > 0 &&
                         (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) {
                 mdelay(1);
@@ -97,7 +100,7 @@ static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data)
 static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data)
 {
         struct timer_list *timer = &alg_data->mif.timer;
-        unsigned long expires = msecs_to_jiffies(I2C_PNX_TIMEOUT);
+        unsigned long expires = msecs_to_jiffies(alg_data->timeout);
 
         if (expires <= 1)
                 expires = 2;
@@ -135,7 +138,7 @@ static int i2c_pnx_start(unsigned char slave_addr,
         }
 
         /* First, make sure bus is idle */
-        if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) {
+        if (wait_timeout(alg_data)) {
                 /* Somebody else is monopolizing the bus */
                 dev_err(&alg_data->adapter.dev,
                         "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n",
@@ -228,7 +231,7 @@ static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data)
                 if (alg_data->mif.len == 0) {
                         if (alg_data->last) {
                                 /* Wait until the STOP is seen. */
-                                if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
+                                if (wait_timeout(alg_data))
                                         dev_err(&alg_data->adapter.dev,
                                                 "The bus is still active after timeout\n");
                         }
@@ -326,7 +329,7 @@ static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data)
                 if (alg_data->mif.len == 0) {
                         if (alg_data->last)
                                 /* Wait until the STOP is seen. */
-                                if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
+                                if (wait_timeout(alg_data))
                                         dev_err(&alg_data->adapter.dev,
                                                 "The bus is still active after timeout\n");
 
@@ -442,7 +445,7 @@ static void i2c_pnx_timeout(unsigned long data)
 
         ctl |= mcntrl_reset;
         iowrite32(ctl, I2C_REG_CTL(alg_data));
-        wait_reset(I2C_PNX_TIMEOUT, alg_data);
+        wait_reset(alg_data);
         alg_data->mif.ret = -EIO;
         complete(&alg_data->mif.complete);
 }
@@ -457,18 +460,18 @@ static inline void bus_reset_if_active(struct i2c_pnx_algo_data *alg_data)
                         alg_data->adapter.name);
                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
                           I2C_REG_CTL(alg_data));
-                wait_reset(I2C_PNX_TIMEOUT, alg_data);
+                wait_reset(alg_data);
         } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) {
                 /* If there is data in the fifo's after transfer,
                  * flush fifo's by reset.
                  */
                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
                           I2C_REG_CTL(alg_data));
-                wait_reset(I2C_PNX_TIMEOUT, alg_data);
+                wait_reset(alg_data);
         } else if (stat & mstatus_nai) {
                 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
                           I2C_REG_CTL(alg_data));
-                wait_reset(I2C_PNX_TIMEOUT, alg_data);
+                wait_reset(alg_data);
         }
 }
 
@@ -612,6 +615,7 @@ static int __devinit i2c_pnx_probe(struct platform_device *pdev)
         struct i2c_pnx_algo_data *alg_data;
         unsigned long freq;
         struct resource *res;
+        u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000;
 
         alg_data = kzalloc(sizeof(*alg_data), GFP_KERNEL);
         if (!alg_data) {
@@ -626,6 +630,22 @@ static int __devinit i2c_pnx_probe(struct platform_device *pdev)
         alg_data->adapter.algo_data = alg_data;
         alg_data->adapter.nr = pdev->id;
 
+        alg_data->timeout = I2C_PNX_TIMEOUT_DEFAULT;
+#ifdef CONFIG_OF
+        alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node);
+        if (pdev->dev.of_node) {
+                of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+                                     &speed);
+                /*
+                 * At this point, it is planned to add an OF timeout property.
+                 * As soon as there is a consensus about how to call and handle
+                 * this, sth. like the following can be put here:
+                 *
+                 * of_property_read_u32(pdev->dev.of_node, "timeout",
+                 *                      &alg_data->timeout);
+                 */
+        }
+#endif
         alg_data->clk = clk_get(&pdev->dev, NULL);
         if (IS_ERR(alg_data->clk)) {
                 ret = PTR_ERR(alg_data->clk);
@@ -651,7 +671,7 @@ static int __devinit i2c_pnx_probe(struct platform_device *pdev)
                 dev_err(&pdev->dev,
                        "I/O region 0x%08x for I2C already in use.\n",
                        res->start);
-                ret = -ENODEV;
+                ret = -ENOMEM;
                 goto out_clkget;
         }
 
@@ -680,14 +700,14 @@ static int __devinit i2c_pnx_probe(struct platform_device *pdev)
          * the deglitching filter length.
          */
 
-        tmp = ((freq / 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
+        tmp = (freq / speed) / 2 - 2;
         if (tmp > 0x3FF)
                 tmp = 0x3FF;
         iowrite32(tmp, I2C_REG_CKH(alg_data));
         iowrite32(tmp, I2C_REG_CKL(alg_data));
 
         iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
-        if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) {
+        if (wait_reset(alg_data)) {
                 ret = -ENODEV;
                 goto out_clock;
         }
@@ -710,6 +730,8 @@ static int __devinit i2c_pnx_probe(struct platform_device *pdev)
                 goto out_irq;
         }
 
+        of_i2c_register_devices(&alg_data->adapter);
+
         dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n",
                 alg_data->adapter.name, res->start, alg_data->irq);
 
@@ -748,10 +770,19 @@ static int __devexit i2c_pnx_remove(struct platform_device *pdev)
         return 0;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id i2c_pnx_of_match[] = {
+        { .compatible = "nxp,pnx-i2c" },
+        { },
+};
+MODULE_DEVICE_TABLE(of, i2c_pnx_of_match);
+#endif
+
 static struct platform_driver i2c_pnx_driver = {
         .driver = {
                 .name = "pnx-i2c",
                 .owner = THIS_MODULE,
+                .of_match_table = of_match_ptr(i2c_pnx_of_match),
         },
         .probe = i2c_pnx_probe,
         .remove = __devexit_p(i2c_pnx_remove),